Yes, definitely the concept of wastage needs to be worked in to forging, which would make the concept of tools/equipment wear much more challenging. This is especially true with novice or unskilled workers; a peasant stuck on the forge is going to make a lot more mistakes and waste a lot more materials than a legendary smith.
I'd like to see something like this worked in to most or all professions (it already is to a degree with mining...better miners produce more stones/minerals), but imagine the potential strategic challenges involved if your farmers or craftsmen waste considerable amounts of resources to produce goods until they are more skilled. Losing, say, three plump helmets out of a stack of five due to unskilled labor would be a brutal issue early-game unless you've got a skilled farmer along with your group.
Of course, this would also be an excellent use of the instructor/observer skills; unskilled dwarves could learn from skilled dwarves not unlike that seen with DF 2010's military system, basically setting up the apprentice/master system that was pretty common at this technology level.
Whether this can be implemented, I'm not certain, but I think it would produce some unique early-game challenges and give higher preference to some previously underutilized skills.